2013年9月12日星期四

Bladder Stones (Urolithiasis) Part 2

Last week I discussed what these stones are and how common they are found in dogs and cats. Bladder stones are formed by minerals, which first precipitate out in the urine as separate microscopic crystals. The most useful diagnostic test used is the urinalysis. Many times these crystals show up in the microscopic analysis of urine and an early diagnosis of the potential of calculi development is determined. The most common type of stone is struvite. These stones are made up of magnesium ammonium phosphate. Other stones are made up of calcium oxalate, calcium phosphate, cystine, ammonium urate, etc. Some stones are a composite of more than one type. This reinforces the importance of a urinalysis, because the treatment varies with the chemical makeup of the crystals. Also, it is very important to determine if an infection is present, as well as the urine pH (level of acidity). Radiographs must be taken to determine the presence of the larger aggregates of minerals called calculi, and their size and location. In males, the size and location of these stones will indicate the risk of obstruction, while in females the small stones in the bladder or urethra can actually pass through the urethra to the outside. One the diagnosis is made, the size and location determined, a decision is made to try or not to try to reduce the size of the stone by means of diet and medication. Sometimes medical therapy is used in conjunction with surgery to treat the patient and eliminate the problem. In males the obstruction potential always looms, so usually surgery is the best choice. The usual associated infection is treated, as well as the correction of pH. The surgical procedure is known as a cytology (my favorite operation). If all the stones are located in the bladder only, and none lodged in the urethra further down the urinary tract, the procedure is very successful, with a quick recovery When the urethra is involved, although the procedure is also very successful, it is more involved, and recovery is longer. Once the immediate problem is resolved, whether by surgery or medical management, the prevention now is the key. We now know that this pet has the genetic capacity of stone production. The type of stone determines which food is recommended to prevent future stones from developing. For instance, struvite producing dogs require a completely different type of food than urate producing dogs. Keeping your pet on the special food is an absolute must. Otherwise, stones will reoccur and surgery has to be repeated. Frequent urine microscopic analysis is very important to determine if any crystals are beginning to form again. Next week my article will be Urolithiasis in Cats. To view more articles, go to my website at http://www.locustvalleyvet.com



没有评论:

发表评论